164 EVENINGS AT THE MICROSCOPE. 



The mode in which they are arranged is in a short spiral, 

 which makes about forty-five whorls or turns about the 

 axis ; at least in the branches which are situated about 

 the middle of the antenna ; for these diminish in length 

 towards the extremity, bringing the feather to a rather 

 abrupt point. 



The entire surface of the branch gleams under reflected 

 light with metallic hues, chiefly yellows and bronzy 

 greens ; which appear to depend on very minute and 

 closely-applied scales that overlap each other. The main 

 stem of the feather, that is, the primary rod or axis, is 

 somewhat sparsely clothed with scales of another kind, 

 thin, oblong, flat plates, notched at the end, and very 

 slightly attached by means of a minute stem at the base, 

 the common clothing-scales of the Lepidoptera, speci- 

 mens of which we have before examined. 



PORTION OF ANTENNA OF OAK EGGER MOTH. 



We may acquire some glimpse of a notion why this 

 remarkable development of antennas is bestowed upon the 

 male sex of this moth, by an acquaintance with its habits. 

 It has long been a practice with entomologists, when they 

 have reared a female moth from the chrysalis, to avail 

 themselves of the instincts of the species to capture the 



